    package com.itheima.interceptors;

    import com.itheima.pojo.Result;
    import com.itheima.utils.JwtUtil;
    import com.itheima.utils.ThreadLocalUtil;
    import jakarta.servlet.http.HttpServletRequest;
    import jakarta.servlet.http.HttpServletResponse;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.data.redis.core.StringRedisTemplate;
    import org.springframework.data.redis.core.ValueOperations;
    import org.springframework.stereotype.Component;
    import org.springframework.web.servlet.HandlerInterceptor;

    import java.util.Map;

    @Component
    public class LoginInterceptor implements HandlerInterceptor {
        @Autowired
        private StringRedisTemplate stringRedisTemplate;
    //使用拦截器统一的对令牌进行验证
        @Override
        public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
    //        令牌验证
            String token = request.getHeader("Authorization");
            try {
//                从redis中获取相同的token，不需要去比较
                ValueOperations<String, String> operations = stringRedisTemplate.opsForValue();
                String redisToken = operations.get("token");

                if (redisToken==null){
//                    token已经失效
                    throw new RuntimeException();
                }
                //            调用工具类解析jwt令牌
                Map<String, Object> claims = JwtUtil.parseToken(token);

    //            把业务数据存储到ThreadLocal中
                ThreadLocalUtil.set(claims);

    //            放行
                return true;
            } catch (Exception e) {
    //            http响应状态码为401，未登录的状态码
                response.setStatus(401);
    //            不放行
                return false;
            }
        }

        @Override
        public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
    //        清空ThreadLocal中的数据,可以放置内存泄漏
            ThreadLocalUtil.remove();
        }
    }
